UNIT CONVERSIONS

MEASUREMENT

3

3

cm

gcm

Dimensional Analysis

The “Factor-Label” Method Units, or “labels” are canceled, or “factored” out

g

Dimensional Analysis

Steps:1. Identify starting & ending units.

2. Line up conversion factors so units cancel.

3. Multiply all top numbers & divide by each bottom number.

4. Check units & answer.

Dimensional Analysis

Lining up conversion factors:

1 in = 2.54 cm

2.54 cm 2.54 cm

1 in = 2.54 cm

1 in 1 in

= 1

1 =

Dimensional Analysis

How many milliliters are in 1.00 quart of milk?

1.00 qt 1 L

1.057 qt= 946 mL

qt mL

1000 mL

1 L

Dimensional Analysis

You have 1.5 pounds of gold. Find its volume in cm3 if the density of gold is 19.3 g/cm3.

lb cm3

Dimensional Analysis

How many liters of water would fill a container that measures 75.0 in3?

=

in3 L

B. Dimensional Analysis

5) Your European hairdresser wants to cut your hair 8.0 cm shorter. How many inches will he be cutting off?

cm in

Dimensional Analysis

6) Hammonton football needs 550 cm for a 1st down. How many yards is this?

cm yd

Dimensional Analysis

7) A piece of wire is 1.3 m long. How many 1.5-cm pieces can be cut from this wire?

m pieces

Dimensional Analysis

8) The speed limit on my street is 35 mph, what is that equivalent to in m/s ?

mi/hr m/s

Dimensional Analysis

9) The Density of Copper is 8.9g/cm3. What is its density in lb/ft3 ?

g/cm3 lb/ft3

Percent Error

Indicates accuracy of a measurement

100literature

literaturealexperimenterror %

your value

accepted value

Percent Error

A student determines the density of a substance to be 1.40 g/mL. Find the % error if the accepted value of the density is 1.36 g/mL.

100g/mL 1.36

g/mL 1.36g/mL 1.40error %

% error =

Proportions

Direct Proportion

Inverse Proportion

xy

xy

1

y

x

y

x